Update to android-mainline kernel headers v5.4.

Update generate_uapi_headers.sh to checkout the android mainline
kernel. Also, add a small modification to look for the kernel directory
in common not linux-stable.

Remove deprecated android headers from android/uapi/linux. Also,
remove f_accessory.h since it's in the android mainline kernel.

Test: Builds and runs on walleye.
Change-Id: Ia371305e19f56e6bcc2db6d5b4d299819f07ffc6
diff --git a/libc/kernel/uapi/linux/videodev2.h b/libc/kernel/uapi/linux/videodev2.h
index e81697e..3d70691 100644
--- a/libc/kernel/uapi/linux/videodev2.h
+++ b/libc/kernel/uapi/linux/videodev2.h
@@ -24,7 +24,7 @@
 #include <linux/types.h>
 #include <linux/v4l2-common.h>
 #include <linux/v4l2-controls.h>
-#define VIDEO_MAX_FRAME 32
+#define VIDEO_MAX_FRAME 64
 #define VIDEO_MAX_PLANES 8
 #define v4l2_fourcc(a,b,c,d) ((__u32) (a) | ((__u32) (b) << 8) | ((__u32) (c) << 16) | ((__u32) (d) << 24))
 #define v4l2_fourcc_be(a,b,c,d) (v4l2_fourcc(a, b, c, d) | (1U << 31))
@@ -414,6 +414,8 @@
 };
 #define V4L2_FMT_FLAG_COMPRESSED 0x0001
 #define V4L2_FMT_FLAG_EMULATED 0x0002
+#define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM 0x0004
+#define V4L2_FMT_FLAG_DYN_RESOLUTION 0x0008
 enum v4l2_frmsizetypes {
   V4L2_FRMSIZE_TYPE_DISCRETE = 1,
   V4L2_FRMSIZE_TYPE_CONTINUOUS = 2,